Given a matching \(M\)  in \(I\) , let \((s_i,p_j) \in (S \times P)\backslash M\)  be a student-project pair, where \(p_j\)  is offered by lecturer \(l_k\) . Then \((s_i,p_j)\)  is a blocking pair of \(M\)  [1]} if 1, 2 and 3 hold as follows:
